U.S. patent application number 10/897876 was filed with the patent office on 2005-04-14 for method and apparatus for automatic configuration of wireless networks.
Invention is credited to Huang, Frank, Nair, Biju, Shu, Zhengjin, Wang, Long, Yu, Chichian.
Application Number | 20050078624 10/897876 |
Document ID | / |
Family ID | 34107803 |
Filed Date | 2005-04-14 |
United States Patent
Application |
20050078624 |
Kind Code |
A1 |
Shu, Zhengjin ; et
al. |
April 14, 2005 |
Method and apparatus for automatic configuration of wireless
networks
Abstract
A wireless network software access point (AP) integrated into a
wireless device allows a wireless network to be configured
automatically and dynamically maintained with minimal user
intervention. Such automatic configuration includes: whether to
configure the Soft AP enabled device to be an AP Node or a Station
Node; specifics of wireless radio link configuration, routing or
bridging relationships with other networking devices attached to
the host-computing device; and firewall configuration. Such
automatic configurations are based on the automatic detection of
the network environment attached to the Soft AP enabled device. The
automatic configurations may also be based on the intelligent
interactions among different Soft AP enabled devices in the
wireless network, which often includes devices with and without
Soft AP functionalities.
Inventors: |
Shu, Zhengjin; (San Jose,
CA) ; Wang, Long; (San Jose, CA) ; Huang,
Frank; (Pleasanton, CA) ; Yu, Chichian; (San
Ramon, CA) ; Nair, Biju; (Buffalo Grove, IL) |
Correspondence
Address: |
PILLSBURY WINTHROP LLP
2475 Hanover Street
Palo Alto
CA
94304-1115
US
|
Family ID: |
34107803 |
Appl. No.: |
10/897876 |
Filed: |
July 22, 2004 |
Related U.S. Patent Documents
|
|
|
|
|
|
Application
Number |
Filing Date |
Patent Number |
|
|
60489399 |
Jul 22, 2003 |
|
|
|
60489408 |
Jul 22, 2003 |
|
|
|
Current U.S.
Class: |
370/328 |
Current CPC
Class: |
Y02D 30/70 20200801;
H04L 41/0806 20130101; Y02D 70/144 20180101; Y02D 70/142 20180101;
H04W 24/02 20130101; Y02D 70/122 20180101 |
Class at
Publication: |
370/328 |
International
Class: |
H04Q 007/24 |
Claims
What is claimed is:
1. A method for dynamically configuring a wireless network
comprising the steps of testing a first wireless node against a
predetermined criteria, establishing the first node as an access
point if the predetermined criteria is satisfied and establishing a
link with a second node, and establishing the first node as a
station node if the predetermined criteria is not met and an
association can be made with an access point.
2. The method of claim 1, further including the step of
establishing the first node as an access point if the predetermined
criteria is not met and no association can be made with an access
point after a predetermined period of time.
3. The method of claim 1, further including the step of
periodically retesting at least some nodes of the network to permit
reconfiguration of the nodes as either access points or station
nodes in accordance with the predetermined criteria.
4. A method of dynamically configuring a wireless network including
the steps of establishing the network among a plurality of nodes by
establishing at least one of the nodes as an access point and at
least one other node as a station node, optimizing the network by
minimizing the number of access points while maintaining a wireless
connection to each node within the network, and extending the
network by connecting to newly added nodes, including reconfiguring
an existing station node as an access point if required to
establish communication with the newly added node.
5. The method of claim 4 further including the step of comparing a
node against a predetermined criteria to determine if the node is
an edge node.
6. The method of claim 4 further including the step of testing a
node against a predetermined criteria to determine whether to
configure that node as an access point or a station node.
7. The method of claim 6 further including the step of periodically
verifying whether the predetermined criteria is still met.
8. The method of claim 7 further including the step of
reconfiguring the node in accordance with whether the predetermined
criteria is still met.
9. The method of claim 6 further including associating a node with
an access point within the network.
10. The method of claim 9 further including testing the association
of a node with a plurality of access points to determine whether to
associate with at least one of the access points.
11. The method of claim 10 further including the step of
configuring a node as an access point if the results of the testing
result in no association being made with a pre-existing access
point.
12. A dynamically reconfigurable network comprising a plurality of
nodes, at least some of the nodes being capable of being configured
as either an access point or a station node, a computer program
resident within at least some of the nodes for testing whether to
establish a given node as an access point or a station node, and a
timer for causing at least one node to rerun the computer
program.
13. The network of claim 12 wherein at least some of the nodes are
not reconfigurable.
14. The network of claim 12 wherein the computer program includes a
predetermined criteria against which performance of a node within
its environment is tested to determine whether to configure that
node as an access point or a station node.
Description
RELATED APPLICATIONS
[0001] This application claims the benefit of and incorporates by
reference U.S. provisional patent applications 60/489,399, filed
Jul. 22, 2003, and entitled Method and Apparatus for Automatic
Configuration of Wireless Networks, and 60/489,408, also filed Jul.
22, 2003, entitled System and Method for Wake on Wireless LAN, and
further is related to commonly owned and concurrently filed U.S.
patent application Ser. No. ______, entitled "System and Method for
Wake on Wireless LAN", attorney docket number 069509-0309910
(client reference PCTEL-13100), which is incorporated herein by
reference in its entirety.
BACKGROUND OF THE INVENTION
[0002] 1. Field of the Invention
[0003] The present invention generally relates to relatively local
distance wireless networks, such as a wireless local area network
(LANs). More specifically, the present invention relates to the
automatic configuration of wireless devices to form relatively
local distance wireless networks, such as the wireless LAN.
[0004] 2. Description of the Prior Art
[0005] In today's relatively local distance wireless networks, as
exemplified by an IEEE 802.11 wireless LAN, a wireless LAN client
station communicates with other wired or wireless LAN client
stations and the Internet through a dedicated wireless LAN access
point (AP). A wireless network is relatively local distance in the
sense that cellular wireless networks are on the large distance
side and other wireless networks, built around standards like IEEE
802.11, HiperLAN, HomeRF, or Bluetooth, are on the local distance
side. The dedicated AP is typically a hardware device that acts as
a communication hub so that users of wireless devices can connect
to the network. Such a dedicated AP is fixed in space and,
therefore, defines a finite coverage area in which the mobile
client stations can roam while still maintaining active
communications within the wireless LAN. Because the location of the
dedicated AP is fixed, a wireless LAN designer must carefully plan
its positioning to both define and maximize the necessary coverage
area of the network.
[0006] Furthermore, multiple dedicated APs are often installed
within one wireless LAN. In at least those commercially available
prior art wireless networks that comply with the 802.11 standard,
each dedicated AP typically serves to relay communications between
client stations and the wired network, which limits their
placement. This interconnected set of dedicated APs will define the
finite coverage area of the wireless LAN. It will be apparent to
those skilled in the art that gaps of lapses in coverage within the
intended coverage area may exist if too few of these dedicated APs
are used or if they are not properly space within the coverage
area. However, having APs located too proximate to one another can
lead to interference and other problems. Therefore, the added
complexity of multiple dedicated APs compounds the problems of
positioning each AP and additionally mandates tedious manual
configuration and maintenance of each AP to achieve the desired
coverage area.
[0007] Therefore, what is needed is a practical method and system
for decreasing the complexity of wireless LAN configuration and
maintenance, while still providing improved coverage and reach.
SUMMARY OF THE INVENTION
[0008] A wireless distribution system and method in accordance with
the present invention provides a flexible, automatically configured
wireless network with extended reach and improved coverage through
the use of a dual mode wireless network software access point (Soft
AP), which can be configured dynamically to function either as a
client station or as a software-based access point with client
station functionality. The dual mode Soft AP device adds
flexibility to the wireless network design by not requiring
dedicated APs, but rather by allowing Soft APs to reside anywhere
within the wireless LAN and to be automatically reconfigured as a
client station or an access point using network intelligence which
analyzes the needs of the network at that location and at that
time. Thus the intelligence of the wireless distribution system of
the present invention may include both a temporal and a physical
component.
[0009] The Soft AP integrated into a wireless device allows a
wireless network to be configured automatically with minimal user
intervention. Such automatic configuration includes: whether to
configure the Soft AP enabled device to be a Station Node or an AP
Node; specifics of wireless radio link configuration, routing or
bridging relationships with other networking devices attached to
the host-computing device; and firewall configuration. Such
automatic configurations are based on the automatic detection of
the network environment attached to the Soft AP enabled device. The
automatic configurations may also be based on the intelligent
interactions among different Soft AP enabled devices in the
wireless network, which often includes devices with and without
Soft AP functionalities.
BRIEF DESCRIPTION OF THE DRAWINGS
[0010] These and other aspects and features of the present
invention will become apparent to those ordinarily skilled in the
art upon review of the following description of specific
embodiments of the invention in conjunction with the accompanying
figures, wherein:
[0011] FIG. 1 shows a broadband gateway according to an embodiment
of the present invention;
[0012] FIG. 2 illustrates a Soft AP device serving as an access
point between wired and wireless devices according to an embodiment
of the present invention;
[0013] FIG. 3 illustrates a wireless bridge between one Soft AP
host and another Soft AP host according to an embodiment of the
present invention;
[0014] FIG. 4 illustrates another wireless bridge between one Soft
AP host and another Soft AP host according to an embodiment of the
present invention;
[0015] FIG. 5 illustrates a network suitable for both a home or
enterprise environment according to an embodiment of the present
invention;
[0016] FIG. 6 illustrates the exemplary generic wireless network
used to show features and aspects of the present invention;
[0017] FIG. 7 illustrates the overall process of automatic
configuration of a wireless network containing the set S of
wireless nodes according to an embodiment of the present invention;
and
[0018] FIG. 8 illustrates the process of self-configuration of the
initially isolated wireless nodes in S to establishing the wireless
network according to an embodiment of the present invention.
DETAILED DESCRIPTION OF THE INVENTION
[0019] The present invention will now be described in detail with
reference to the drawings, which are provided as illustrative
examples of the invention so as to enable those skilled in the art
to practice the invention. Notably, the figures and examples below
are not meant to limit the scope of the present invention.
Moreover, where certain elements of the present invention can be
partially or fully implemented using known components, only those
portions of such known components that are necessary for an
understanding of the present invention will be described, and
detailed descriptions of other portions of such known components
will be omitted so as not to obscure the invention. Further, the
present invention encompasses present and future known equivalents
to the known components referred to herein by way of
illustration.
[0020] Overview
[0021] In the typical wireless LAN, a device is either manually
configured to be a dedicated access point (AP) or manually
configured to be a client station, and does not have the
functionality of both. In the present invention, a wireless device
includes a software AP (Soft AP). Such a wireless device is said to
be Soft AP capable. The Soft AP capable device contains the
functionality of both a client station and a wireless LAN AP, and
can be configured to emulate one or the other, or both, at any
given time.. The Soft AP can function with a variety operating
systems (e.g., Windows, Linux, Unix, Lindows, MacOS, etc.) and on a
variety of wireless devices (e.g., Desktops, Laptops, Personal
Digital Assistants, etc.). Further, the Soft AP of the present
invention can either be host-based or not; that is, the Soft AP
will either use the host device processor or its own processor to
perform its software functions.
[0022] In one embodiment of the present invention the Soft AP is
designed to function in a Windows environment. In this exemplary
embodiment, the Soft AP is a dual mode Network Interface Card (NIC)
with a Network Driver Interface Specification (NDIS) NIC miniport
driver and an NDIS intermediate driver. The NIC miniport driver
supports both standard NDIS services as well as Object Identifier
(OID) functions for the wireless LAN. The NDIS intermediate driver
is designed to work with a wireless LAN device and is built with
both station and access point capabilities in its Media Access
Control (MAC) layers. The wireless device operating with the Soft
AP will be registered with the device operating system as a network
adapter.
[0023] Using devices configured with the Soft AP within a wireless
LAN has dramatically increased the flexibility of a traditional
wireless LAN using only dedicated APs. A Soft AP capable device, as
in the present invention, can replace some or all of the dedicated
APs. This replacement results in a more flexible and dynamic
coverage area, as the Soft AP devices are typically mobile and can
be either an AP or a client station as needed. Note that throughout
this disclosure, whenever the Soft AP is referred to as being an
AP, it is meant that the Soft AP is performing the functions of the
traditional dedicated AP while at the same time allowing the device
to be used as a client station. Whenever the Soft AP is acting as a
client station, it is only performing those functions typically
associated with a client station.
[0024] The reduced cost and increased flexibility of the Soft AP
solution, as contrasted to dedicated APs, will inevitably result in
their increased use within existing wireless LANs, until there are
an overabundance of AP-capable wireless devices (i.e., the
dedicated APs plus the additional Soft AP devices) to complete the
wireless LAN within the given environment. This means that some of
these AP-capable wireless devices might need to be configured as
APs while others are not. Furthermore, as Soft APs are mobile
devices, it is no longer feasible to select a static group of
AP-capable devices to be dedicated APs for the Soft AP mobile
environment.
[0025] Another aspect of the present invention arises when a
wireless LAN contains a large number of AP-capable wireless devices
and not all of these devices are required to be configured as an AP
to achieve certain networking goals of the wireless LAN, such as
maximizing the overall throughput of the entire network. In this
situation, only a selected number of the Soft AP devices might need
to be configured as APs to complete the wireless LAN, with the
remaining Soft AP devices acting as mobile clients. Additionally,
as the mobile Soft AP devices move within the wireless LAN or as
new mobile Soft AP devices are added to the wireless LAN, the
selection between AP or non-AP configuration necessarily changes
over time.
[0026] Therefore, the present invention provides a wireless network
Soft AP integrated into a wireless device allowing a wireless
network to be configured automatically and dynamically maintained
with minimal user intervention. The Soft AP includes the necessary
drivers (e.g., AP, client, WDS, bridging, etc.) and the protocol
routing, firewall and Dynamic Host Configuration Protocol (DHCP)
server functions. The automatic configuration includes: whether to
configure the Soft AP enabled device to be an AP Node or a Station
Node; specifics of wireless radio link configuration, routing or
bridging relationships with other networking devices attached to
the host-computing device; and firewall configuration. Such
automatic configurations are based on the automatic detection of
the network environment attached to the Soft AP enabled device. The
automatic configurations may also be based on the intelligent
interactions among different Soft AP enabled devices in the
wireless network, which often includes devices with and without
Soft AP functionalities.
[0027] Having provided this overview of the basic structure of the
present invention, the details of the invention will now be
presented.
[0028] Broadband Gateway
[0029] FIG. 1 shows a broadband gateway according to an embodiment
of the present invention. As shown in FIG. 1 according to one
aspect of this embodiment, the broadband gateway enables wireless
devices PC 1 (120) and PC 2 (130) to connect to the Internet
wirelessly through the Soft AP network interface (103) inside PC 0
(100) via the Ethernet interface (102) and the broadband modem
(110). According to another aspect of this embodiment, broadband
gateway can include protocol routing, firewall and DHCP server
functions (101), such as those provided by the Microsoft Internet
Connection Sharing (ICS) if PC 0 (100) runs a Microsoft Windows
operating system. Note that the "PC" designation used in the
drawings should in no way limit the scope of the present invention.
As will be obvious to those skilled in the art in view of this
disclosure, each "PC" designated device can be any wireless network
device, such as a laptop, PDA or cell phone, that is capable of
utilizing the Soft AP of the present invention.
[0030] As an example of this embodiment of the present invention, a
Microsoft Internet Connection Sharing (ICS) enables the wireless
device Internet connection. In this broadband Internet gateway,
when ICS is enabled on the Ethernet interface (102) serving the
Soft AP network interface (103), an IP address, like 192.168.0.1,
is assigned to the Soft AP network interface (103). PC 1 (120) and
PC 2 (130) can then obtain dynamic IP addresses, like 192.168.0.x,
once their wireless LAN cards are associated with the Service Set
Identifier (SSID) of the Soft AP (103). Further, the wireless LAN
cards of PC 1 (120) and PC 2 (130) could also be Soft AP network
interfaces functioning in client station mode. However, the ICS
between the Soft AP network interface (103) and the wired Ethernet
interface (102) must still be set up, either manually and
independently of Soft AP or automatically and dynamically as part
of Soft AP.
[0031] Ethernet to Soft AP Bridge
[0032] FIG. 2 illustrates a Soft AP device serving as an access
point between wired and wireless devices according to an embodiment
of the present invention. As sown in FIG. 2, the Soft AP host PC 3
(200) acts as a wireless access point for wireless PC stations
(220, 230), bridging them to wired PC stations (240, 250). Such a
MAC layer bridge (202) of the present invention merges the wireless
LAN with the wired LAN by bridging the wired Ethernet interface
(201) and the Soft AP network interface (203). This bridge forms a
single logical LAN of all PC stations, including the Soft AP host
PC 3 (200). Any PC station in this logical wireless LAN may act as
a DHCP server (e.g. PC 4, 240). However, the bridging (202) between
the Soft AP network interface (203) and the wired Ethernet
interface (201) must still be set up, either manually and
independently of Soft AP or automatically and dynamically as part
of Soft AP.
[0033] Note that the bridge (202) between the wireless and the
wired networks of PC stations are transparent to Layer 3 protocols
such that a wireless PC station on one side of the Soft AP host PC
3 (200) can directly talk to a wired PC station on the other side
of the Soft AP host PC 3 (200) without going through a layer 3
proxy or gateway.
[0034] An example of this embodiment of the present invention
includes a Windows XP built-in MAC Bridge Miniport Driver that can
be used to bridge the Ethernet network interface (201) and the Soft
AP network interface (203).
[0035] Wireless Bridge
[0036] FIG. 3 illustrates a wireless bridge (302) bridging one Soft
AP host PC 8 (300)-to another Soft AP host PC 0 (100) according to
the present invention. As shown in FIG. 3, the Soft AP (303) in the
far-end (i.e., relative to the broadband gateway, 100) host PC 0
(100) is used as a wireless bridging access point, serving wireless
PC stations (320, 330), which are too far to associate with the
near-end Soft AP (103) of the broadband gateway PC 0 (100). Such a
wireless bridge (302) might, for example, be done in the MAC layer
implementing a Wireless Distribution System (WDS). This wireless
bridge (302) merges the wireless LAN associated with the Soft AP
network interface (303) in PC 8 (300) with the wireless LAN
associated with the Soft AP network interface (103) in PC 0 (100).
This merges the two wireless LANs associated, respectively, with
the two Soft AP's (103, 303) into a single logical LAN, and all
wireless stations (120, 130, 320, 330) in this single logical LAN
can access the Internet through the broadband gateway PC 0 (100).
For instance, PC 10 (330) can talk to PC 1 (210) directly without
going through a layer 3 proxy or gateway. This single logical
wireless LAN expands that of FIG. 1, extending the wireless reach
of the Soft AP (103) hosted in PC 0 (100).
[0037] FIG. 4 illustrates another wireless bridge (402) bridging
one Soft AP host PC 8 (300) to another Soft AP host PC 3 (200)
according to the present invention. As shown in FIG. 4, the Soft AP
(303) in the far-end (i.e., relative to the wired LAN access, 200)
host PC 8 (300) is used as a wireless bridging access point,
serving wireless PC stations (320, 330), which are too far to
associate with the near-end Soft AP (203) of the wired LAN access
PC 3 (200). Again, the two Soft AP's (203, 303) might, for example,
form a WDS in the MAC layer, that bridges (402) between the wired
and the wireless sides in PC 3 (200) to form a single logical LAN
that includes all PC stations, wired or wireless, far or near,
relative to the wired section of the logical LAN (240, 250). This
single logical LAN expands that of FIG. 2, extending the wireless
reach of the Soft AP (203) hosted in PC 3 (200).
[0038] The WDS in FIG. 3 (or that in FIG. 4) by itself forms a LAN
with its two constituent Soft APs (103 and 303 in FIG. 3, 203 and
303 in FIG. 4) as the network nodes. Such a WDS LAN is bridged in
layer 2 with the two wireless LANs associated with the two
respective Soft APs (103 and 303 in FIG. 3, 203 and 303 in FIG. 4)
forming a single logical wireless LAN that has farther reach than
either of the two physical wireless LANs separately. Of course, the
wireless throughput from a wireless PC station in one physical
wireless LAN to a wireless PC station in the other physical
wireless LAN will be cut in half as the link goes through two
access points as opposed to through only one access point for a
single physical wireless LAN. Note that in this discussion, the
wireless LAN associated with a single access point is referred to
as a physical wireless LAN, and the wireless LAN merged through a
wirelessly bridged LAN is referred to as a logical wireless
LAN.
[0039] A Home or Enterprise Network
[0040] FIG. 5 illustrates a network suitable for both a home or
enterprise environment according to the present invention. Such a
network is a combination of the network segments depicted and
discussed in FIG. 1 through FIG. 4, above. As shown in FIG. 5, PC 0
(100) is the broadband access gateway. PC 1 (120) through PC 10
(330) form a single logical LAN behind the gateway (100), merging
wired PC stations (240, 250) with several groups of wireless
stations (120, 130, 200, 220, 230, 300, 320, 330) via both
Ethernet-to-AP and wireless bridges. Note that PC 1 (501) through
PC 10 (510) could be any wireless network capable device, such as a
laptop, PDA or cell phone, and are not meant to be limited by the
"PC" nomenclature. FIG. 5 is discussed in further detail,
below.
[0041] Network and Device Configuration
[0042] An embodiment of the present invention presents methods and
systems for the automatic configuration of wireless local area
networks (LANs). This disclosure uses an exemplary generic wireless
network to illustrate the features and aspects of this embodiment
of the present invention. Those skilled in the art will recognize
that the disclosures herein can easily be applied to other network
types, and such applications are meant to be within the scope of
the present invention.
[0043] FIG. 6 illustrates the exemplary generic wireless network
used to show features and aspects of the present invention. As
shown in FIG. 6, the generic wireless network consists of a set S
(indicated at 600) of wireless network devices, or nodes, indicated
generally at 605, that communicate with neighboring nodes 605
wirelessly. The relative positions among the nodes 605 may change
from time to time and the number of nodes 605 in the set S changes
over time as well. Each wireless network device 605 behaves either
as a Station Node, indicated at 610, or an Access Point (AP) Node,
indicated at 615. A Station Node 610 communicates with other
wireless nodes only through first communicating with an AP Node
615. That is, there is no Station Node to Station Node direct
wireless communication in the exemplary generic wireless
network.
[0044] Station Node communication is possible only after it is
associated with an AP Node. Further, a Station Node 610 can be
associated with only one AP Node 615 at any given time. An AP Node
615 communicates directly with neighboring AP nodes 615 and to
Station Nodes 610 that are associated to it. In this way, the AP
Node 615 serves as a relay station for other AP Nodes 615 and other
Station Nodes 610 attempting to communicate wire lessly with a
particular Station Node 610 that is associated to it. Therefore,
within the exemplary generic wireless network, any node, or device,
in the network can communicate with any other node through one or
more AP Nodes 615.
[0045] Within the set S of wireless devices of the exemplary
generic wireless network, there is a subset S.sub.AP-capable,
indicated at 620, of nodes that are capable of behaving either as
an AP Node or as a Station Node, for example, the subset
S.sub.AP-capable nodes 620 might be Soft AP nodes, indicated at
625. In the context of wireless networks, and as previously
discussed, a Soft AP node 625 is defined as a device that can be
configured as either a wireless client station or a wireless AP.
They can be configured dynamically, or automatically, to be an AP
Node 615 or a Station Node 615 depending on the communication needs
among all the wireless nodes in S.
[0046] Automatic, or dynamic, configuration of the wireless nodes
in S means that each wireless network node can be automatically
configured such that the wireless network can be formed. Such
automatic configuration of each wireless devise can involve many
aspects, including: configuring a node to be an AP Node or a
Station Node if that node is AP-capable; for Station Nodes,
configuring the node to associate with a neighboring AP Node to
establish a direct wireless link between that Station Node and the
wireless network; and for AP Nodes, configuring the node to
establish a direct wireless link with a selected number of
neighboring AP Nodes in the wireless network using, for example,
the Wireless Distribution System (WDS).
[0047] In one embodiment, the present invention can be implemented
as a piece of software that runs on each wireless node and can
configure the host device accordingly, such that the wireless
network S can be formed and maintained indefinitely. A wireless
node automatically configures itself to behave a certain way by
running the software implementation of the present invention on the
device to configure it to behave as such. Therefore, automatic
configuration can also be referred to as self-configuration.
Likewise, when the wireless nodes in S configure themselves
automatically, the wireless network S self-configures.
[0048] According to one aspect of an embodiment of the present
invention, the wireless network of nodes in S may need to be
authenticated and authorized to be part of S by some means. One
such means according to an embodiment of the present invention uses
the concept of network identification. In this embodiment, the set
S of wireless nodes have the same network identification ID.sub.S.
Such a network identification ID.sub.S is defined to include a set
of network parameters that are necessary for a wireless network
node to become part of S. For example, in the case of a wireless
LAN, the network parameters might include the Service Set
Identifier (SSID) and the Wired Equivalent Privacy (WEP) key. In
other words, wireless network nodes already in S have means to know
if a particular wireless node that comes into range of S is
authorized to join the network S.
[0049] Thus, assuming the wireless network nodes in S can be
properly authenticated and authorized to be part of S, a key aspect
of this embodiment of the present invention is concerned with how a
group of originally isolated wireless network nodes in S with the
same ID.sub.S can form the wireless network, and how this wireless
network can be maintained by actions taken by the individual nodes
in S, while optimizing the wireless network performance according
to certain criteria C.sub.NETWORK, illustrated in FIG. 7. The
criteria C.sub.NETWORK are a set of conditions against which a
wireless node can test, such that if C.sub.NETWORK is met for the
node, the configuration of the node is considered to be
satisfactory in the sense that such configuration will remain the
same until C.sub.NETWORK is no longer valid for the node. An
example of such a criterion in C.sub.NETWORK is to minimize the
number of nodes that need to be configured as AP nodes, under the
condition that all wireless nodes must have the same ID.sub.S and
be within the range of S. Another example is to maximize the
overall throughput of the wireless network formed by the devices in
S. A third example might be whether the node can reach the
Internet; another might be whether the node can reach a particular
server on the network included in S. Yet another example is,
assuming a particular node is configured as an AP Node, whether
there is any other node that has been associated to it as a Station
Node within a specified time limit. When such a time limit expires
without a Station Node associating to it, the AP Node can configure
itself as a Station Node and scan for an available AP Node in
range.
[0050] FIGS. 7 and 8 illustrate the overall process of automatic
configuration of a wireless network containing the set S of
wireless nodes 605 and can be decomposed into three phases that
reflect three different goals. The first phase, indicated at 700,
is to initiate or establish the wireless network. The second phase,
at 710 is to optimize the wireless network after it has been
established. The third phase, indicated at 720, is to extend the
wireless network. Automatic configuration of the wireless network
is an on-going process, which may dynamically shift from one phase
to another with minimal disruption to the existing network
connections of S. Each of these three phases is discussed in
further detail below.
[0051] Establishing the Wireless Network
[0052] FIG. 8 illustrates the process of self-configuration of the
initially isolated wireless nodes in S to establishing the wireless
network. For this aspect of the present invention, assume that the
set S of wireless nodes all have the same network identification
ID.sub.S and initially are each isolated from all others nodes, as
indicated at 800. The process of connecting initially isolated
nodes into a wireless network corresponds to the phase of
establishing the wireless network, shown generally at 700 in FIG.
7. The purpose of establishing the wireless network is for the
nodes in S to self-configure such that C.sub.NETWORK can be met for
each node by forming a wireless network. All nodes in S will
simultaneously perform the initial network establishment procedure.
The process of establishing the wireless network also applies to
the still isolated nodes when the other nodes in S are already
connected with one another wirelessly (i.e., when part of the
wireless network has been established and there is still an
isolated node that needs to join the network).
[0053] Without initially being connected to any other node
wirelessly, a wireless node in S will first check to see whether
C.sub.NETWORK is met, as indicated at 810. If C.sub.NETWORK is met,
that node configures itself as an AP Node until C.sub.NETWORK is no
longer met, as indicated at 815. Such an AP Node is labeled as a
master AP node. If C.sub.NETWORK is not met, as indicated at 820,
that node scans for an AP Node, as indicated at 825, for a maximum
time period of T.sub.SCAN as indicated at 830. If no AP Node is
found, that node also configures itself as an AP Node, as shown at
815. One characteristic of C.sub.NETWORK according to the present
invention is that C.sub.NETWORK can be different depending on
whether a node is configured as an AP Node or a Station Node.
[0054] Each of those nodes that have configured themselves as AP
Nodes without meeting their corresponding criteria C.sub.NETWORK
will stay in the initially established configuration for a time
period of T.sub.ESTABLISH, as indicated at 730 in FIG. 7, during
which, it periodically checks for other newly established AP Nodes
in range. Whenever there is another AP Node in range, it will setup
a direct wireless link (e.g., a WDS link) with that in-range AP
Node with itself staying configured as an AP Node, as shown at 835
in FIG. 8.
[0055] If there are one or more AP Nodes in range during scanning,
as indicated at 840, that node will configure itself as a Station
Node as indicated at 845 and associates with these in-range AP
Nodes one at a time and checks if C.sub.NETWORK is met as indicated
at 850. If C.sub.NETWORK is met when associated with a particular
AP Node, it will stay associated with that AP Node, as shown at
840. If C.sub.NETWORK is not met by associating with any of the AP
Nodes, as shown at 855, then that node configures itself as an AP
Node and sets up a direct wireless link (e.g., a WDS link) with all
other AP Nodes in range.
[0056] As previously mentioned, every time a node configures itself
as an AP Node, it will stay in the AP mode for a period of
T.sub.ESTABLISH. After this period expires, if C.sub.NETWORK is
still not met, it will restart the T.sub.ESTABLISH timer and stay
in the AP mode for another period, as shown generally at 725. The
number of T.sub.ESTABLISH cycles an AP Node goes through without
ever meeting C.sub.NETWORK is recorded and can be used as a
condition for changing to a different C.sub.NETWORK, which change
may be aided by input from the user of the wireless device after
first providing such condition information to the user. When
C.sub.NETWORK is met by the end of a T.sub.ESTABLISH period, the
node goes into the network optimization phase, as shown in FIG. 7
at 730.
[0057] Optimizing the Network
[0058] According to an embodiment of the present invention, the
process of optimizing the network attempts to minimize the number
of AP Nodes in S, while maintaining the connectivity among all of
the nodes in S and the integrity of the wireless network.
[0059] As shown in FIG. 7, during optimization, an AP Node
disconnects its direct wireless link (e.g., a WDS link) with
another AP Node if such a disconnection does not invalidate
C.sub.NETWORK. If an AP Node only has one direct wireless link with
only one other AP Node, it will signal all of the Station Nodes
associated with it to try to re-associate with another AP Node. If
all of the associated Station Nodes can and do re-associate with
another AP Node, without invalidating their own C.sub.NETWORK, the
original AP Node will have no Station Nodes associated with it, yet
still have the one direct wireless link to another AP Node. When an
AP Node has no associated Station Nodes and no more than one direct
wireless link to another AP Node, it will reconfigure itself as a
Station Node and associate with the AP Node to which it had its
sole direct wireless link.
[0060] Extending the Network
[0061] In a further embodiment of the present invention, a node
configured as a Station Node that is located on the edge, or
coverage periphery, of the wireless network periodically
reconfigures itself as an AP Node for a period of T.sub.BRIDGE,
while setting up and maintaining a direct wireless link (e.g. a WDS
link) with the AP Node it had been associated with before switching
from a Station Node to an AP Node. This periodic reconfiguration is
controlled by another time period TEXTEND, as shown in FIG. 7 at
735. While in the T.sub.BRIDGE period acting as an AP Node, it
waits for other Station Nodes to associate with it, or other AP
nodes to link to it. If after this T.sub.BRIDGE period no such
associations and no direct wireless links are created, it
reconfigures itself back to being a Station Node, as shown at
740.
[0062] A Station Node is said to be an edge Station Node if the
criteria C.sub.EDGE are met. The criteria C.sub.EDGE are defined as
a set of conditions for a Station Node to test against that
reflects how far a Station Node is from a master AP node. One such
condition is a distance measure reflected by the number of hops, or
relays among AP Nodes, there are between the Station Node and the
master AP Nodes. Another condition is the signal strength between
the Station Node and the immediate AP Node to which it is
associated. If the signal strength is too weak (e.g., below a
certain predefined threshold), then the Station Node may be
considered as an edge Station Node. A third example of such a
condition is the combination of the number of hops a Station Node
must go through to reach a master AP Node and the signal strengths
between the relaying AP Nodes.
[0063] Node Configuration
[0064] Another embodiment of the automatic configuration of the
present invention is the detailed node configuration required after
a node in S switches from being a Station Node to an AP Node and
vice versa. Such detailed node configuration can, for example,
include the specifics of wireless radio link configuration, routing
or bridging relationships with other networking devices, wired and
wireless, attached to the device, and firewall configuration.
[0065] As previously discussed, FIG. 5 illustrates a typical
wireless home or enterprise network enabled, at least in part, by
Soft AP devices and other related technologies according to the
present invention. As shown in FIG. 5, PC 0 (100) is the broadband
gateway with broadband access (120). PC 1 (120) through PC 10 (330)
form a single logical LAN behind the gateway (100), merging wired
devices (240, 250) with several groups of wireless devices (120,
130, 200, 220, 230, 300, 320, 330) via both Ethernet-to-AP and
wireless bridges. Again, note that PC 1 (120) through PC 10 (330)
could be any wireless network capable device, such as a laptop, PDA
or cell phone, and are not meant to be limited by the "PC"
nomenclature.
[0066] With reference to FIG. 5, assume that in the network shown a
subset of the PC stations (e.g. 100, 130, 200, 220, 300) are Soft
AP capable wireless devices and the rest of the wireless devices
have only a traditional wireless LAN client card installed. Manual
configuration and setup for the wireless links for both the Soft AP
capable devices and the wireless client devices can be a
challenging task, especially when not every wireless device can
reach all other wireless devices. In this situation some kind of
radio planning must be involved.
[0067] In the traditional wireless network, manual radio planning
is necessary to place and install the dedicated access points and
wireless repeaters at strategic locations. However, in the Soft AP
enabled wireless network (i.e., when Soft AP capable devices make
up at least a subset of the total wireless devices in the wireless
network), such radio link setups can be automated without user
intervention. This is possible because Soft AP is natively
interfaced to its host device and therefore is under full control
of the host device. This control makes it possible to easily
install the necessary software in the host device to dynamically
configure selected Soft AP capable devices into either the AP mode
or the wireless client mode. The dynamic configuration is based, at
least in part, on the quality of the radio links among all wireless
devices and on the dynamic bridging and/or routing needs of the
wireless network.
[0068] In addition to automatic radio planning link setups of the
wireless portion of the network, a Soft AP enabled wireless network
allows automatic IP network configuration and diagnostic, and
application profile management, further simplifying that task of
setting up wireless or mixed wired and wireless networks. It is
worth noting, however, that the foundation for such higher-level
automations is the ability of automatic configuration of wireless
radio links enabled by the Soft AP technology.
[0069] Although the present invention has been particularly
described with reference to the preferred embodiments thereof, it
should be readily apparent to those of ordinary skill in the art
that changes and modifications in the form and details thereof may
be made without departing from the spirit and scope of the
invention. For example, those skilled in the art will understand
that variations can be made in the number and arrangement of
components illustrated in the above block diagrams. It is intended
that the appended claims include such changes and
modifications.
* * * * *